The Process of In Vitro Fertilization (IVF)

体外受精(IVF)イメージ

In Vitro Fertilization – Embryo Transfer (IVF-ET) is, the way that in which the developed oocyte just before ovulation are collected from the ovaries and are allowed to be fertilized in the culture solution, making them to some extent the same as an oocyte being fertilized and developed in the womb. There might be some of those labeled as a “test-tube baby” in the past, having the image of special treatment. However, the little bit of help to the small part of the complex process of a complete pregnancy is IVF-ET.

It does of course require a high degree of skill in fertilization and culture, but in recent years it has not just been a special treatment but is becoming one of the common treatments.

So, let’s take a look at to see just what kind of thing is the IVF-ET.

IVF-ET Case Natural Pregnancy Case

1)Ovulation Induction

In order to efficiently collect the oocytes, we can grow many oocytes by use of oral medicine and injections.
Alternatively, there is also the way of waiting for the oocytes to grow naturally, without any ovulation induction.

 

Follicles develop by the action of the hormone (LH, FSH) that is secreted into the blood.

2)Oocyte Pick-up, Semen Collection

The oocytes are collected by inserting a needle into the ovary. ( It is a simple surgery that can be completed in a few hours) Semen will be collected on the day of oocytes retrieval.採卵・採精説明イラスト

 

Ovulation (Usually only one)

3)Insemination

Although there are a number of ways, the most basic of these is the (conventional) method of waiting for the adjusted concentration of sperm that has been sprinkled on the oocyte to be fertilized.
There is also the way of injecting the sperm into the oocyte using a fine needle while looking through a microscope (Combined fertilization = ICSI).

 

The oocyte and sperm meet at the end of the fallopian tubes, while dividing taking several days after fertilization, the oviduct is moved.

By the time it reaches the uterus it has become a blastocyst.

After ovulation the bag the oocyte was in changes to corpus luteum, and begins production of progesterone.

4)Embryo Transfer

The fertilized oocyte is called the embryo. The embryo that had become 4-8 cells by cell division is then put into the uterus by embryo transfer.
Additionally, there is also the method of continuing to culture it In Vitro until it has become a blastocyst and then placing it into the uterus.

5)Corpus Luteum Activiation

Supplemented with progesterone (a hormone that facilitates implantation) by an injection or oral medicine.

IVF-ET is done according to the menstrual cycle. There are several ways in each stage and there are many a number of patterns based on the combination thereof.
I will introduce the most standard IVF-ET in our clinic.

Menstruation – Day 1

Treatment Starts

Start to use the nasal spray called Buserelin. This is intended to suppress the secretion of hormones into the body to prevent a spontaneous ovulation. Continue usage until two days before oocyte Pick-up.

Menstruation - Day 3

Ovulation Induction

Although there is a situation where from the fifth day of menstruation to use oral medicine to stimulate ovulation, we usually grow follicles (the bag the oocyte are in) by use of a hormone shot. From the sixth day of menstruation we will measure the size of the follicle with ultrasound and adjust the amount of the hormone serum.

If follicles around 20mm in diameter multiply, we will inject HCG, the hormone that stimulates the maturation of the oocyte. It is said that there will be ovulation after 36 hours of the HCG injection. Therefore, at our clinic, we will inject the HCG at night and then oocyte Pick-up the morning after the next day.

Menstruation – Day 10˜ 18

Oocyte Pick-up

As for the oocyte Pick-up, it will be done while looking through the microscope and sticking a needle into the ovary. It is like a very simple day surgery. We use anesthesia during oocyte Pick-up so that there is neither pain nor fear.

Semen Collection

On the day of oocyte Pick-up, we will also take a sample of your husband’s semen. The semen entrusted to us will have a concentrated wash with a special washing solution, and then we will collect only the sperm with good motility.

Fertilization

To allow the fertilization, we will culture the embryos on the afternoon on the day of oocyte Pick-up.

The most basic (a.k.a. “conventional”) method is waiting for the adjusted concentration of sperm that has been sprinkled on the oocyte to be fertilized. In addition, there is also the Combined Fertilization (ICSI) where while looking through the microscope a thin needle is used to place one sperm directly into the oocyte.

We will determine beforehand by counseling which method to use by looking at the data of past treatments and semen samples.

Conventional

We will sprinkle the sperm that has been adjusted to the appropriate concentration on to the oocyte that is in the state of being covered by a cell. The sperm will melt the cell around the oocyte, and by the power of the sperm will penetrate the cell.

コンベンショナル画像

ICSI (Intra Cytoplasmic Sperm Injection)

To the oocytes that have detached the surrounding cell by enzyme treatment, a single sperm will be injected by needle insertion while looking under the microscope.

Fertilization Confirmation · Culture

Whether you use conventional fertilization or ICSI fertilization, both will develop in the same way.
If fertilization goes well, we will be able to see two nuclei within the embryo cell. This is the “male pro-nucleus” derived from sperm and the “female pro-nucleus” derived from the oocyte. Fertilization is complete when the two pro-nuclei are fused together.
The one cell (embryo) that comes from the fusion of the sperm and oocyte will then have repeated cell division and soon emerges as new life.

前核期 核融合 2分割 4分割 8分割 胚盤胞
Pronuclear Fusion Divided into 2 Divided into 4 Divided into 8 Blastocyst

The IVF-ET growth process is watched over and while recording it in detail is carefully cultured until implanted into the uterus.

After Oocyte Pick-up – Day 2

Embryo Transfer (ET)

The embryo transfer will take place two days after the oocyte Pick-up when the embryo has developed to the point that it has divided about 4 to 8 times. While looking at the data and having vigorous meetings with the doctor and embryologist, only the best embryos will be selected to implant into the uterus. In some cases, with a little longer culture period, we may transfer the oocyte Pick-up when they have reached blastocyst stage, at around the fifth to sixth day (Blastocyst Transfer=BT). We usually transfer only up to two blastocysts, in order to avoid multiple pregnancies. In the case of there being a surplus it is recommended to undergo cryopreservation (freeze-preservation). If you didn’t get pregnant after trying IVF-ET the first time and you still desire a second child, the burden on the body will be less if we defrost and transfer another embryo.
We will supplement with progesterone hormone by use of an injection or oral medicine in order to help the implantation of the embryos implanted after transplantation of the embryo (blastocyst).

胚移植画像

After Oocyte Pick-up Day 18

Pregnancy Decision

Test for pregnancy.

Though there are many methods in the treatment of infertility, none of them are the absolute way and unfortunately it doesn’t mean that even the IVF-ET will be successful. Infertility treatment is something that you can only challenge again and again, and on top of that the fact of the matter is that it is difficult to succeed in this as one gets older.

Based on that fact, our clinic thinks that IVF-ET to be a very effective measure. All of our staff hopes that we can provide all the assistance needed to all of those who are hoping for a child.